反应详情

温度

24 °C

To a solution of (S)-4-dibenzofuran-2-yl-4-oxo-2,2,2-trifluoroacetylamino)-butyric acid (1.0 g, 0.0026 mol) from Example 1 in 50 mL of methanol was added sodium acetate trihydrate (1.08 g, 0.0079 mol). The solution was stirred at 24° C. while an aqueous solution (5 mL) of hydroxylamine hydrochloride (0.37 g, 0.00527 mol) was added in one portion. The reaction mixture was stirred for 3 hours at 24° C., and then heated to reflux for 2 hours. The solution was cooled to 24° C. and concentrated to dryness by evaporation under reduced pressure. The solid was rinsed with 10 mL of water, and crystallized from ethyl acetate and hexane to afford 0.13 g of (S)-4-dibenzofuran-2-yl-4-hydroxyimino-2-(2,2,2-trifluoroacetylamino)-butyric acid; mp 128-130° C.

1. additionwas added in one portion
2. temperatureheated
3. temperatureto reflux for 2 hours
4. temperatureThe solution was cooled to 24° C.
5. concentrationconcentrated to dryness by evaporation under reduced pressure
6. washThe solid was rinsed with 10 mL of water
7. customcrystallized from ethyl acetate and hexane